Examples:
The following VBA example deletes the active layer and moves all shapes on the active layer to the next layer on the page.
Sub Test()
Dim Target As Layer
Dim s As Shape
Dim idx As Long
If ActivePage.Layers.Count = 1 Then
MsgBox "Cannot delete a single layer"
End If
If ActiveLayer.Shapes.Count Then
idx = 1 ' Determining the index number of the active layer
For Each Target In ActivePage.Layers
If Target Is ActiveLayer Then Exit For
idx = idx + 1
Next Target
' Finding the index number of the target layer
If idx = 1 Then idx = 2 Else idx = idx - 1
Set Target = ActivePage.Layers(idx)
ActiveDocument.ClearSelection
ActiveLayer.Shapes.All.AddToSelection
ActiveSelection.Layer = Target
End If
ActiveLayer.Delete
End Sub